document.write( "<A HREF=/cgi-bin/jump-to-question.mpl?question=204427>Question 204427</A>This question is from textbook <A HREF=http://www.amazon.com/exec/obidos/ASIN/0321331796/algebrahomeworkh></A><BR>\n" );
document.write( ": <I><SPAN STYLE=\"word-break: break-all;\"> At a party, 28 handshakes took place. Each person shook hands exactly once with each of the others present. How many people were at the party.? </SPAN>\n" );
document.write( "</I><HR><TABLE width=100%><TR><TD><B><A HREF=http://www.algebra.com/>Algebra.Com's</A> Answer #154340 by </B><A HREF=/tutors/aboutme.mpl?userid=scott8148><B>scott8148(6628)</B></A><img src=\"/images/stars/stars-13.gif\" alt=\"\" >&nbsp;<A HREF=/tutors/aboutme.mpl?userid=scott8148><IMG SRC=http://www.algebra.com/images/aboutme-small.gif BORDER=0 alt=\"About Me\" VALIGN=MIDDLE></A>&nbsp;<IMG SRC=http://www.algebra.com/cgi-bin/show-face.mpl?user=scott8148><BR>You can <A HREF=\"/cgi-bin/embed-solution.mpl?show=1&solution=154340\">put this solution on YOUR website!</A><BR><SPAN STYLE=\"word-break: break-all;\"> a couple of important thoughts ...<BR>\n" );
document.write( "___ you don't shake hands with yourself<BR>\n" );
document.write( "___ Bill shaking hands with Sue is the same as Sue shaking hands with Bill\r<BR>\n" );
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document.write( "so, N people shake hands with N-1 people ___ and half of the handshakes are duplicates\r<BR>\n" );
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document.write( "28 = N(N-1) / 2 ___ 56 = N(N-1) ___ 8 * 7 = N(N-1) ___ 8 = N\r<BR>\n" );
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document.write( "this can also be evaluated by using nC2 and solving for n </SPAN>\n" );
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